The late Sen. Daniel Patrick Moynihan famously remarked that, “The central conservative truth is that it is culture, not politics, that determines the success of a society. The central liberal truth is that politics can change a culture and save it from itself.”

It’s true that culture is more important than politics. You could impose Sweden’s laws on the Middle East tomorrow, but you’d be well-advised not to hold your breath waiting for the Saudis to turn into the Swedes of the Arabian Peninsula.

But it’s also true that politics — specifically, government — can change cultures. It can be loud and bloody work, as with the abolition of slavery. Or the change can be more subtle. Twenty years ago, it was simply uncool to put on your seat belt. Now, everyone seems to do it reflexively. The law changed the culture, for the better.

Still, my biggest problem with Moynihan’s insight is that he didn’t think it all the way through. The “liberal truth” that politics can change a culture and save it from itself is double-edged. For just as politics can save the culture, politics can also destroy it.

Which brings me to Thomas Lopez, a 21-year old lifeguard in South Florida.

Two days before the Fourth of July, Lopez was fired for helping rescue a man drowning 1,500 feet outside of his designated zone.

“It was a long run, but someone needed my help. I wasn’t going to say no,” Lopez told the South Florida Sun-Sentinel.

When Lopez filed his incident report, he was canned on the spot.

“They didn’t tell me in a bad way. It was more like they were sorry, but rules are rules,’“ Lopez said. “I couldn’t believe what was happening.”

The contractor that manages the lifeguard service has explained that the matter is out of their hands, too. Liability issues — i.e., fear of lawsuits, insurance requirements, etc. — demand a zero-tolerance policy for unauthorized lifesaving.

It’s a small anecdote to be sure. But does anyone doubt that there’s something about the legal regime in this country that’s creating a headwind against basic human decency? And I’m not just talking about trial lawyers and the politicians who love them.

Last year, in Alameda, Calif., a man walked into the chilly — but not exactly freezing — waters of the Bay Area to commit suicide. It was a slow affair. The police and firefighters got there in plenty of time. But, due to union-backed rules, they simply declined to save the man’s life. They just stood on the beach and watched.

Fire Chief Ricci Zombeck was asked what he would have done if it were a child, rather than a suicidal adult, slowly drowning out there. He responded that if he were on duty he’d have let the kid drown, but if he was off duty he would have saved him.

These are the symptoms of a sick culture.

These days, liberals are celebrating the moral triumph of their health-care reform. We’re helping the uninsured! We’re making government more humane and compassionate. And from one perspective, that’s all true, I suppose.

But we’re also changing the culture. In some areas it’s obvious. For instance, religious institutions are being bullied into compliance with ObamaCare. In other ways the changes are far more subtle, even invisible (though if you follow the British media coverage of their state-run health system, you get a hint of what’s coming; prepare for ever more debates about rationing, denying treatment to the “unworthy,” euthanasia and the rest).

House Minority Leader Nancy Pelosi sold ObamaCare on the grounds that it would be culturally liberating. People no longer would be “job-locked” because of health care, she explained. So, “if you want to be creative and be a musician or whatever, you can leave your work” and pursue your dreams.

And if your dream is to be a fireman, a lifeguard or, perhaps very soon, a doctor who isn’t allowed to save lives, you may not have to leave your job at all. But if that’s not your dream, get ready for a headwind.